The present invention provides a process for producing C2-C4 olefins from
methanol and
ethanol, comprising: A) feeding a feed
stream A containing
methanol, with or without
ethanol, to a
dimethyl ether fixed-
bed reactor to catalytically convert the
methanol to
dimethyl ether to obtain a product
stream A1 containing
dimethyl ether, methanol,
ethanol, and
water vapor; B)
Stream A1 is mixed with at least one
hydrocarbon recycle
stream R containing C2-C6 hydrocarbons and treated in an olefin
fixed bed reactor to produce C2-C4 olefins, C5-C6 hydrocarbons and C7 + catalytically converting the
hydrocarbon-containing crude product stream B into a crude product stream B comprising hydrocarbons; C) cooling crude product stream B to obtain
hydrocarbon crude product stream C; D) separating the hydrocarbon crude product stream C into a valuable product stream comprising propylene, optionally a valuable product stream comprising
ethylene, a valuable product stream comprising butenes, at least one C5-C6 hydrocarbon-containing recycle stream, and a C6 + separating the hydrocarbon-containing by-product stream into at least one by-product stream; E) recycling a portion of the C2-C4 olefins and at least a portion of the C5-C6 hydrocarbons to step B) as one or more hydrocarbon recycle streams; F) obtaining a valuable product stream comprising propylene, a valuable product stream comprising
ethylene, and optionally a valuable product stream comprising butenes; G)C6 + disposing of said by-product stream comprising hydrocarbons; Including, the methanol- and ethanol-based stream A contains less than 1% by weight or 30% to 50% by weight of ethanol, in which case 30% to 60% by weight of
ethylene, 30% to 60% by weight of propylene and 0% to 30% by weight of butenes are obtained as valuable products, based on 100% by weight of C2-C4 olefins, and furthermore 0% to 40% of said ethylene, 40% to 90% of said propylene and 0% to 100% of said butenes, based on the C2-C4 olefins present in the crude product stream B, are recycled to step B); Alternatively, the methanol and ethanol based stream A comprises 1% to 30% by weight of ethanol, in which case 0% to 20% by weight of ethylene, 70% to 100% by weight of propylene and 1% to 20% by weight of butenes are obtained as valuable products, based on 100% by weight of C2-C4 olefins, and further 0% to 100% by weight of said ethylene, 0% to 20% by weight of said propylene and 40% to 100% by weight of said butenes, based on the C2-C4 olefins present in the crude product stream B, are recycled to step B).